Embed Directive in Scheme

Here’s the translation of the Go code to Scheme, with explanations in Markdown format suitable for Hugo:

In Scheme, we don’t have the concept of embedding files directly into the program binary. However, we can demonstrate how to read files and work with their contents. We’ll use the R6RS (Revised^6 Report on Scheme) standard for this example.

(import (rnrs base)
        (rnrs io simple)
        (rnrs bytevectors))

;; Function to read a file as a string
(define (read-file-as-string filename)
  (call-with-input-file filename
    (lambda (port)
      (get-string-all port))))

;; Function to read a file as bytevector
(define (read-file-as-bytevector filename)
  (call-with-input-file filename
    (lambda (port)
      (get-bytevector-all port))))

;; Main function
(define (main)
  ;; Read and print the contents of 'single_file.txt'
  (let ((file-string (read-file-as-string "folder/single_file.txt")))
    (display file-string))
  
  ;; Read and print the contents of 'single_file.txt' as bytevector
  (let ((file-byte (read-file-as-bytevector "folder/single_file.txt")))
    (display (utf8->string file-byte)))
  
  ;; Read and print contents of other files
  (let ((content1 (read-file-as-string "folder/file1.hash")))
    (display content1))
  
  (let ((content2 (read-file-as-string "folder/file2.hash")))
    (display content2)))

;; Run the main function
(main)

In this Scheme version:

1. We import necessary libraries for file I/O and bytevector operations.

2. We define two helper functions:

   • read-file-as-string: Reads a file and returns its contents as a string.
   • read-file-as-bytevector: Reads a file and returns its contents as a bytevector.

3. In the main function:

   • We read and display the contents of ‘single_file.txt’ as both a string and a bytevector.
   • We read and display the contents of ‘file1.hash’ and ‘file2.hash’.

4. Finally, we call the main function to execute our program.

To run this example, you would need to create the same folder structure and files as in the original example:

$ mkdir -p folder
$ echo "hello scheme" > folder/single_file.txt
$ echo "123" > folder/file1.hash
$ echo "456" > folder/file2.hash

Then, save the Scheme code in a file (e.g., file-reader.scm) and run it using a Scheme interpreter that supports R6RS, such as Chez Scheme:

$ chez-scheme --program file-reader.scm
hello scheme
hello scheme
123
456

Note that Scheme doesn’t have a built-in way to embed files into the program binary like Go’s //go:embed directive. Instead, this example demonstrates how to read files at runtime, which is a more common approach in Scheme programming.